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1.
The effects of a biquadratic exchange and an external magnetic field on the phase states of a twodimensional non-Heisenberg ferromagnet have been studied with allowance for magnetoelastic and magnetodipolar interactions.  相似文献   
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The structure of the nonlinear H-filter in the neighborhood of the estimated trajectory is investigated and a bound on the size of the neighborhood that allows this structure is determined, both for finite and infinite horizons. Riccati inequalities that depend on the estimated trajectory are derived for finding the filter gain matrix and an algorithm for calculating the bound on the size of the above neighborhood is presented. Explicit formulas are obtained in the infinite horizon case for the minimum achievable disturbance attenuation level, the size of the neighborhood, and the corresponding filter gain.  相似文献   
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With the aim of classifying PVC materials in which surface layers are converted into interpenetrated network cyclam nanofilms among polymer-polymer systems, comparative studies of their properties were carried out with consideration for the specific conditions for the preparation of the material. The density and structures of near-surface layers, the bulk ratio of the ordered and disordered forms, the dynamics of swelling in water, and the effective partial volume occupied by water molecules were studied for PVC plates prior to and after hydrothermal treatment. The conversion of the surface layers changes the structural self-organization of PVC: the polymer structure becomes more compact and ordered both in the area adjacent to the nanofilm and in the polymer bulk, which is characteristic of systems of the type “hard coating on soft substrate”. Original Russian Text ? A.Ya. Fridman, E.M. Morozova, A.Yu. Tsivadze, N.P. Sokolova, I.I. Bardyshev, A.M. Gorbunov, O.P. Shapokhina, 2007, published in Zashchita Metallov, 2007, Vol. 43, No. 5, pp. 498–502.  相似文献   
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The method of rapid heating of the medium was used for investigating the dependence of the viscosity of polyvinyl chloride plastisols on the temperature and time in connection with isothermal molding in casting practice.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 51, No. 4, pp. 609–613, October, 1986.  相似文献   
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We report the characterization of amphiphilic aminoglycoside conjugates containing luminophores with aggregation-induced emission properties as transfection reagents. These inherently luminescent transfection vectors are capable of binding plasmid DNA through electrostatic interactions; this binding results in an emission “on” signal due to restriction of intramolecular motion of the luminophore core. The luminescent cationic amphiphiles effectively transferred plasmid DNA into mammalian cells (HeLa, HEK 293T), as proven by expression of a red fluorescent protein marker. The morphologies of the aggregates were investigated by microscopy as well as ζ-potential and dynamic light-scattering measurements. The transfection efficiencies using luminescent cationic amphiphiles were similar to that of the gold-standard transfection reagent Lipofectamine® 2000.  相似文献   
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The solid solution decomposition of Alnico 5 and Alnico 8 is studied by means of electron microscopy and X-rays. The following sequence of the decomposition process is found: Alnico 5: spherical zones-periodic modulated structure-rod-shaped particles of metastable tetragonal phases-final cubic phases; Alnico 8: the same sequence, but due to great importance of elastic energy at the decomposition, the three-dimensional modulated structure forms even during sharp quenching. The kinetics of modulated structure formation is studied. It is shown that the modulation wavelength increases according to a (time)nlaw. The activation energies of the decomposition process are determined. The spinodal mechanism of decomposition of the alloys in question is discussed.  相似文献   
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